The within invention concerns a camera for recording an image information.
Cameras of this type are widely known, for example as photo cameras, movie cameras, or even TV cameras. Cameras of this type customarily contain a recording medium on which the image information is stored in specified manner. In the case of, for example a photo camera containing a color film, the image information, that is, the photographed subject, is stored in specified nature and manner that can depend on the camera itself and also on the recording medium. This stored information is then reproduced in the laboratory, for example on photographic paper. In the case of color films, the image information is customarily subdivided into several partial spectral ranges, that is, for example, into red, green, and blue ranges. This spectral distribution can be achieved by photographing with color filters, or, as is customary today, with films having three superimposed layers, each sensitive to one-third of the visual spectrum.
In the case of black-and-white photography, there is no such spectral distribution of the image information to partial ranges. However, here the image information is stored on the recording medium in the form of brightness graduations, that is, in the form of levels of intensity.
In the recording of colored image information, the problem is that the spectral ranges of the recording medium must be developed or reproduced in such manner that the natural coloring of the recorded image information is reproduced. In the reproduction of the image information, care must therefore be taken to ensure that the image is not blue-, green-, or red-tinted, something that could occur if in the development of the film the corresponding spectral ranges of the recording medium were insufficiently exposed. In a color film this defect can be caused by, for example, the fact that the color layer sensitive to the blue spectral range is old and has correspondingly less sensitivity. In development of a film of this type by means of a standard development process, this leads to a situation in which the blue segment of the recorded image is too limited in the reproduction, which means that the reproduced image is green- or red-tinted.
The said effect can also occur when, for example, in a digital camera the components sensitive to different spectral ranges are exposed to different temperatures and thus react with different sensitivities. If an image recorded with a camera of such type is reconstructed, the problem described above occurs again, namely, the color weight does not accord with that of the subject originally photographed.
With black-and-white films the problem is that the brightness of the reproduction does not accord with the brightness of the subject photographed, that is, the luminance of the reproduced image is too high or too low, so the image is too bright or too dark.